Which breeds should be avoided together?
I have silkies and ameraucana that get along fairly well but are kept in separate pens. Had barred rocks that tried to kill the silkies and beat up the ameraucana. Brahma did fine with ameraucana. New Hampshire were so so.
Some breeds are aggressive and others very laid back. Always read up on a breed and it's temperament.
Breeds with big crests like silkies or polish can't even seen the attacks when they come